ADI AD5220BNZ100

The AD5220 provides a single channel, 128-position digitally controlled variable resistor (VR) device. This device performs the same electronic adjustment function as a potentiometer or variable resistor. These products were optimized for instrument and test equipment push-button applications. A choice between bandwidth or power dissipation are available as a result of the wide selection of end-to-end terminal resistance values. The AD5220 contains a fixed resistor with a wiper contact that taps the fixed resistor value at a point determined by a digitally controlled UP/DOWN counter. The resistance between the wiper and either end point of the fixed resistor provides a constant resistance step size that is equal to the end-to-end resistance divided by the number of positions (e.g., R_STEP = 10 kΩ / 128 = 78 Ω). The variable resistor offers a true adjustable value of resistance, between the A terminal and the wiper, or the B terminal and the wiper. The fixed A-to-B terminal resistance of 10 kΩ, 50 kΩ or 100 kΩ has a nominal temperature coefficient of 800 ppm/°C. The chip select CS, count CLK and U/D direction control inputs set the variable resistor position. These inputs that control the internal UP/DOWN counter can be easily generated with mechanical or push button switches (or other contact closure devices). External debounce circuitry is required for the negative-edge sensitive CLK pin. This simple digital interface eliminates the need for microcontrollers in front panel interface designs. The AD5220 is available in both surface mount (SO-8) and the 8-lead plastic DIP package. For ultracompact solutions selected models are available in the thin μsOIC package. All parts are guaranteed to operate over the extended industrial temperature range of -40°C to +85°C.

• 128 Position
• Potentiometer Replacement
• 10 kΩ, 50 kΩ, 100 kΩ
• Very Low Power: 40 μA Max
• Increment/Decrement Count Control
• Qualified for automotive applications

• Mechanical Potentiometer Replacement
• Remote Incremental Adjustment Applications
• Instrumentation: Gain, Offset Adjustment
• Programmable Voltage-to-Current Conversion
• Programmable Filters, Delays, Time Constants
• Line Impedance Matching
• Power Supply Adjustment